Question

Bỏ dấu ngoặc rồi thu gon:

( a- b)-(a-b-c)-(2b+c-a)

Answer 1

( a - b ) - ( a - b - c ) - ( 2b + c - a )

= a - b - a - b - c - 2b + c - a

= a - a - a - b - b - 2b - c + c

= a - 2b 

Answer 2

= a - b - a + b + c - 2b - c + a

= a - 2b

Answer 3

a-2b

k cho tớ nha

Answer 4

(a-b)-(a-b-c)-(2b+c-a)

=a-b-a+b+c-2b-c+a

=a-2b

Answer 5

Ta có:

( a - b)-( a - b - c )-(2b + c - a)

= a - b - a + b + c - 2b - c +a

= (a-a) +( -b+b) +(c-c) + ( -2b +a)

= -2b+a

Answer 6

Bỏ dấu ngoặc và thu gọn:

\(\left(a-b\right)-\left(a-b-c\right)-\left(2b+c-a\right)\)

\(=a-b-a+b+c-2b-c+a\)

\(=\left(a-a+a\right)+\left(-b+b-2b\right)+\left(c-c\right)\)

\(=a+\left(-2b\right)+0\)

\(=a+\left(-2b\right)\)

\(=a-2b\)